Surgeons perform tens of thousands of operations each year to resect suspicious lung nodules. Historically this necessitated an open surgical approach (thoracotomy) through a large chest wall incision. Over the last 10-15 years, minimally invasive surgical (MIS) approaches have become increasingly common in abdominal and thoracic surgery, with significant benefits accruing to both patients and healthcare economics. However, one key aspect of open surgery is missing in MIS: direct tissue palpation (touch). While a mere nuisance for many MIS procedures, the loss of tactile feedback is critically important during thoracoscopic lung biopsies and resections as it is very difficult to detect nodules beneath the lung surface. This significantly increases the risk of missing a nodule and can force the surgeon to abandon the minimally invasive approach, open the chest, and perform direct manual palpation. Pre-operative techniques to nodule localization have been used with varying success, but all involve complex CT-guided marking and bulky intraoperative instruments. Engineers and scientists have undertaken the technical challenge of restoring palpation in MIS. An array of devices is described in the literature, and many are indeed capable of locating hidden nodules. Significantly, however, none is in common use;they are cumbersome, potentially injurious, difficult to interpret, and expensive. When surgeons need to feel for nodules during MIS, they resort to enlarging the incision and sticking a finger into the hole. In this research project, we will test the ability of a new three-dimensional image acquisition technology to provide real-time "visual palpation" for sub-surface lung nodules. The eventual goal of the program is to offer a medical video camera product that, combined with common operating room equipment, provides the first practical, intuitive, immediate, and low cost means of non-touch palpation in MIS. A recently developed opto-electronic device acquires high-resolution 3D topographic data at video frame rates through standard medical scopes. By deflecting the lung surface inward with a momentary gas jet, relatively harder nodules located below the surface will alter the deflection of the overlying tissue and be seen as aberrations in the surface topography. The 3D topographic data can be analyzed and enhanced for display in real time to the surgeon, immediately and intuitively revealing the hidden nodule. The specific aims of this project are (1) design and fabricate a small gas-jet probe that connects to a medical insufflator, (2) write custom software for topographic analysis to tag surface aberations created by hidden nodules, and (3) test the system on excised animal and human lung tissue. PUBLIC HEALTH RELEVANCE: Surgery to remove cancerous lung nodules from saves lives. The preferred minimally invasive surgical approach can miss nodules when they have grown beneath the surface of the lung. This project strives to develop and test a practical, intuitive, and low-cost 3D image acquisition and analysis solution to the problem of locating hidden lung nodules.